There was a review of the myocarditis issue in young people associated with the mRNA vaccines today.
In the end, the biggest risk group by far is
males from 12-24 years old, where it occurs in about 1 in 20k vaccinations after dose 2. Hospitalization is basically a given it sounds like, but patients
generally do well (there are still two in the ICU though, out of several hundred cases!).
Symptoms usually show within the first week, most commonly within 4 days. However, it can take a bit longer in some cases. Chest pain is the most common symptom with shortness of breath much more rare.
The reaction is more common with Moderna than with Pfizer (about twice as common it appears), though data is limited for Moderna so far.
These rates seem lower than those that I have seen reported in papers from Israel (but have not looked closely at that), but they are still quite high indeed in these age groups.
Here's the most relevant presentation:
At these rates, in these age groups,
the risk of COVID is clearly still much higher (hundreds of people in these age groups have died to date, and who knows how much other damage has been done).
ACIP Presentation slides from June 23-25, 2021 meeting. Advisory Committee on Immunization Practices (ACIP).
www.cdc.gov
View attachment 676814
Obviously they'll continue to try to figure out why this is happening. If I had a child around the age of 12-18, I would go for Pfizer, I guess. There have been relatively few vaccinations of young people (12 and up) so far, so we'll see how this goes.
Here's where we stand on estimated IFRs though; looks like about 1 in 30k or so for very young people and maybe 1 in 10k or so for people in their 20s, from COVID. Obviously hospitalization rates are much higher... "Just the flu." (Definitely appears that except PERHAPS for age 5-12, COVID is substantially worse than even the worst influenza. The rates in 0-5 group are not obvious in this chart, but looking at the CDC data you can see outcomes are not great in this age group as compared to 5-12.)
View attachment 676804